Non-cardiac Chest Pain in Japan: Prevalence, Impact, and Consultation Behavior - A Population-based Study

Background/Aims@#Non-cardiac chest pain (NCCP) is defined as recurring angina-like retrosternal chest pain of non-cardiac origin. Information about the epidemiology of NCCP in Japan is lacking. We aim to determine the prevalence and characteristics of NCCP in the Japanese general population. @*Methods@#Two internet-based surveys were conducted among the general population in March 2017. Questions investigated the characteristics of symptoms associated with chest pain and consultation behavior. Quality of life, anxiety, depression, and gastroesophageal reflux disease were analyzed. @*Results@#Five percent of the survey respondents reported chest pain. Subjects with chest pain showed higher frequencies of anxiety and depression and lower quality of life. Among subjects with chest pain, approximately 30% had sought medical attention for their symptoms. Among all consulters, 70% were diagnosed with NCCP. Females were less likely to seek consultations for chest pain than males. Further, severity and frequency of chest pain, lower physical health component summary score, and more frequent gastroesophageal reflux disease were associated with consultation behavior. Subjects with NCCP and cardiac chest pain experienced similar impacts on quality of life, anxiety, and depression. Among subjects with NCCP, 82% visited a primary-care physician and 15% were diagnosed with reflux esophagitis. @*Conclusions@#The prevalence of chest pain in this sample of a Japanese general population was 5%. Among all subjects with chest pain, less than one-third consulted physicians, approximately 70% of whom were diagnosed with NCCP. Sex and both the severity and frequency of chest pain were associated with consultation behavior.

Yokukansan Suppresses Gastric Hypersensitivity and Eosinophil-associated Microinflammation in Rats With Functional Dyspepsia

Background/Aims@#Herbal medicine is an important complementary therapy for functional dyspepsia (FD). However, its effect against gastric hypersensitivity in patients with FD has rarely been evaluated. Yokukansan (YKS), a traditional Japanese herbal medicine, is effective against neuropathic and inflammatory pain. This study aims to use a maternal separation (MS) stress-induced FD model to investigate the effects of YKS against gastric hypersensitivity, gastric motility, and duodenal micro-inflammation. @*Methods@#The MS stress model was established by separating newborn Sprague-Dawley rats from their mothers for 2 hours a day from postnatal days 1 to 10. At the age of 7-8 weeks, the rats were treated with YKS at a dose of 5 mL/kg (1 g/kg) for 7 consecutive days. AfterYKS treatment, electromyographic activity in the acromiotrapezius muscle by gastric distention and the gastric-emptying rate were assessed. Immunohistochemical analysis of eosinophils in the duodenum and phosphorylated extracellular signal-regulated kinase(p-ERK) 1/2 in the spinal cord was performed. @*Results@#YKS treatment suppressed MS stress-induced gastric hypersensitivity and decreased the elevated levels of p-ERK1/2 in the spinal cord.In the gastroduodenal tract, YKS inhibited eosinophil-associated micro-inflammation but did not improve gastric dysmotility. @*Conclusions@#YKS treatment improved gastric hypersensitivity by alleviating eosinophil-associated micro-inflammation in the gastroduodenal tract.This treatment may be considered an effective therapeutic option for epigastric pain and micro-inflammation in patients with FD.

A Randomized Double-blind Placebo-controlled Trial on the Effect of Magnesium Oxide in Patients With Chronic Constipation

BACKGROUND/AIMS: Magnesium oxide (MgO) has been frequently used as a treatment for chronic constipation (CC) since the 1980s in Japan. The aim of this study is to evaluate its therapeutic effects of MgO in Japanese CC patients. METHODS: We conducted a randomized, double-blind placebo-controlled study. Thirty-four female patients with mild to moderate constipation were randomly assigned to either placebo (n = 17) or MgO group (n = 17) 0.5 g × 3/day for 28 days. Primary endpoint was overall improvement over the 4-week study period. Secondary endpoints were changes from baseline in spontaneous bowel movement (SBM), response rates of complete spontaneous bowel movement (CSBM), stool form, colonic transit time (CTT), abdominal symptom, and quality of life. RESULTS: One patient failed to complete the medication regimen and was omitted from analysis: data from 16 placebo and 17 MgO patients were analyzed. The primary endpoint was met by 25.0% of placebo vs 70.6% of MgO group (P = 0.015). MgO significantly improved SBM changes compared to placebo (P = 0.002). However, MgO did not significantly improved response rates of CSBM compared to placebo (P = 0.76). In addition, MgO significantly improved Bristol stool form scale changes (P < 0.001) and significantly improved CTT compared to the placebo group (P < 0.001). MgO significantly improved the Japanese version of the patient assessment of constipation quality of life (P = 0.003). CONCLUSION: Our placebo-controlled study demonstrated that MgO was effective treatment for improving defecation status and shortened CTT in Japanese CC patients with mild to moderate symptoms.

Current Status and Issues of Education on Radiation Health Risk Science / 医学教育

In accordance with the new model-core-curriculum for medical education, the current status of education about the science of radiation health was surveyed in all medical schools in Japan. Among the four learning points related to the “Biological effects of radiation and radiation hazards” , about half of the schools covered issues on “radiation and human body” and the “effect of medical radiation exposure” in one, or less than one, 60-minutes class, but did not touch on “radiation risk communication” and “radiological disaster medicine” . A significant deviation of human resources was also observed between schools. Learning tools such as presentation files and video content were preferred as education support materials. Therefore, development and distribution of the learning tools, especially in “radiation risk communication” and “radiological disaster medicine” , may be a first step to promoting high-quality education on the science of radiation health risk in each school’s curriculum.

Prevalence of Gastric Motility Disorders in Patients with Functional Dyspepsia

BACKGROUND/AIMS: Gastric motility abnormalities have been considered to be pathophysiological features of functional dyspepsia (FD) that are closely related to dyspepsia symptoms, especially postprandial distress syndrome (PDS). The aims of this study are to (1) investigate the prevalence of gastric motility disorders and (2) evaluate the association between gastric motility abnormalities and dyspeptic symptoms using gastric scintigraphy in the PDS type of FD. METHODS: Forty healthy subjects and 94 PDS type FD patients were enrolled in the study. The volunteers and patients ingested a radiolabeled (technetium-99m) solid test meal, and scintigraphic images were recorded. Gastric accommodation and emptying were assessed by scintigraphic imaging. The patients’ dyspeptic symptoms were also explored using self-completed symptom questionnaires with 10 variables (4 scales, 0–3 points) at the same time. RESULTS: In 94 Japanese FD patients, the prevalence of impaired gastric accommodation and delayed emptying were 14.9% (14/94) and 10.6% (10/94), respectively. Gastric motility abnormalities were seen in 25.5% (24/94) of FD patients. There was no association between gastric motility abnormalities and dyspeptic symptoms. CONCLUSIONS: Gastric motility abnormalities were seen in 25.5% of Japanese PDS type FD patients. However, there was no association between gastric motility abnormalities and dyspeptic symptoms on gastric scintigraphy.

Intravenous Corticotropin-releasing Hormone Administration Increases Esophageal Electrical Sensitivity in Healthy Individuals

BACKGROUND/AIMS: When a person is experiencing stress, corticotropin-releasing hormone (CRH) can modulate gut physiologies, such as visceral sensation or gastrointestinal motility, and its intravenous administration mimics stress-induced physiological changes. However, the influence of CRH on the esophagus is yet unknown. Accordingly, we investigated whether intravenous CRH administration increases esophageal sensitivity to electrical stimulation in healthy Japanese subjects. METHODS: Twenty healthy subjects were recruited. We quantified the initial perception threshold (IPT) every 15 minutes after CRH injection. Venous blood was collected with a cannula, and both plasma adrenocorticotropic hormone (ACTH) and cortisol were measured at pre-stimulation, 0, 30, 60, 90, and 120 minutes. The results from each time point were compared against a baseline IPT obtained before electrical stimulation was initiated. RESULTS: When compared to the baseline IPT value (16.9 ± 4.5), CRH significantly decreased electrical threshold of the esophagus at 30, 45, 60, 75 minutes (14.1 ± 4.2, 13.1 ± 5.0, 12.1 ± 5.7, 14.0 ± 5.8 minutes, P < 0.01, respectively) after CRH injection, suggesting that CRH increased esophageal sensitivity to the electrical stimulus. CRH also significantly increased plasma ACTH levels at 30 minutes (50.3 ± 17.7, P < 0.01), and cortisol levels at 30 minutes (22.0 ± 6.7 minutes, P < 0.01) and 60 minutes (20.3 ± 6.7 minutes, P < 0.01) after CRH injection, when compared to the pre-stimulation ACTH and cortisol values. CONCLUSION: Intravenous CRH administration increased esophageal electrical sensitivity in normal subjects, emphasizing the important role of stress in esophageal sensitivity.

Prevalence of Irritable Bowel Syndrome–like Symptoms in Japanese Patients with Inactive Inflammatory Bowel Disease

BACKGROUND/AIMS: Few studies are available that have investigated the risk factors for overlapping irritable bowel syndrome (IBS)-like symptoms in patients with inactive inflammatory bowel disease (IBD). The present study has 3 objectives: (1) to assess the prevalence of IBS-like symptoms in Japanese patients with inactive IBD using Rome III criteria, (2) to examine the relationship of IBS-like symptoms to health related quality of life (HR-QOL), and (3) to investigate associations for developing IBS-like symptoms in patients with inactive IBD. METHODS: IBS-like symptoms were evaluated using the Rome III questionnaire for functional gastrointestinal disorders. HR-QOL and hospital anxiety and depression scale were evaluated. RESULTS: IBS-like symptoms were found in 17.5% (7/40) of patients with inactive ulcerative colitis, 27.1% (29/107) of patients with inactive Crohn’s disease (CD), and 5.3% (23/438) of healthy control subjects. The QOL level was significantly lower and anxiety score was significantly higher in inactive CD patients with IBS-like symptoms than in those without such symptoms (P = 0.003, P = 0.009). Use of anti-anxiety drugs was associated with the presence of IBS symptoms (P = 0.045). HR-QOL score was lower and anxiety score was higher in patients with inactive ulcerative colitis, but the difference was not statistically significant. CONCLUSIONS: The prevalence of IBS-like symptoms in inactive IBD patients was significantly higher than in healthy controls. Inactive CD patients with IBS-like symptoms has low QOL and anxiety; suggesting that anxiety may be associated with symptom development in such patients.

Prevalence and Self-recognition of Chronic Constipation: Results of an Internet Survey

BACKGROUND/AIMS: Although chronic constipation is a common symptom, to date no international consensus has been reached regarding its definition. The aims of this study were (1) to investigate defecation habits and (2) to examine the prevalence of constipation using the Japanese Society of Internal Medicine (JSIM) and the Rome III criteria using an online survey. METHODS: An online questionnaire composed of items on the frequency, interval, form of defecation, the management, and self-recognition of constipation (reference standard of constipation) was created. A total of 5155 valid responses were received. In addition, constipation symptoms were evaluated through a survey using the JSIM and the Rome III criteria. RESULTS: In the internet survey, 28.4% of the respondents considered themselves to be constipated. Stratified by sex, significantly more females (37.5%) than males (19.1%) considered themselves to be constipated (P < 0.001). The prevalence of constipation among the respondents was 28.0% using the Rome III, but only 10.1% using the JSIM. The diagnostic accuracy was 73.2% for the Rome III and 78.1% for the JSIM, while the diagnostic specificity was 81.1% for the Rome III and 97.5% for the JSIM. However, the diagnostic sensitivities for both measures were low, at 52.2% and 29.2% for the Rome III and the JSIM, respectively. CONCLUSIONS: The online survey developed for this study was able to provide clarification regarding defecation patterns. The results also suggest a discrepancy between the self-recognized prevalence of constipation in Japan and prevalence of constipation based on the JSIM criteria.

Esophageal Sensation and Esophageal Hypersensitivity: Overview From Bench to Bedside

Noxious stimuli in the esophagus activate nociceptive receptors on esophageal mucosa, such as transient receptor potential, acid-sensing ion channel and the P2X family, a family of ligand-gated ion channels responsive to ATP, and this generates signals that are transmitted to the central nervous system via either spinal nerves or vagal nerves, resulting in esophageal sensation. Among the noxious stimuli, gastric acid and other gastric contents are clinically most important, causing typical reflux symptoms such as heartburn and regurgitation. A conventional acid penetration theory has been used to explain the mechanism of heartburn, but much recent evidence does not support this theory. Therefore, it may be necessary to approach the causes of heartburn symptoms from a new conceptual framework. Hypersensitivity of the esophagus, like that of other visceral organs, includes peripheral, central and probably psychosocial factor-mediated hypersensitivity, and is known to play crucial roles in the pathoegenesis of nonerosive reflux disease, functional heartburn and non-cardiac chest pain. There also are esophagitis patients who do not perceive typical symptoms. This condition is known as silent gastroesophageal reflux disease. Although the pathogenesis of silent gastroesophageal reflux disease is still not known, hyposensitivity to reflux of acid may possibly explain the condition.